Adjustable ski stick



8 m m "0 L n TN N 4 NW. m 9 E 4, Wm w 2 0 Z r A 9 paw 4 w M .W Z a fl/a. y f Y B O- W. JENSEN ADJUSTABLE SKI-STICK Flled Sept 28 1948 Jan. 17,1950 Patented Jan. 17, 1950 ADJUSTABLE SKI STICK Ole Walter Jensen,Skollei'udveien Pr. Sandvika, Norway Application September 28, 1948,Serial No. 51,499 In Norway March 13, 1948 3 Claims. (Cl. 287-58) Thepresent invention relates to an adjustable ski-stick consisting of twotelescopically sliding tubes and the invention is characterized chieflyby the two tubes being firmly locked to each other by the pressure of anon-springy frictional clamp,

placed loosely in a case or holder in such a way that it is radiallymovable.

Several types of adjustable ski-sticks have been brought on the marketand most of them utilize a split, springy, frictional device, the prongsof which are pressed out by means of a conical spindle to create thefrictional pressure required. Other constructions use springy tongues orprotruding pins which fit into grooves. The two parts are lockedtogether by the resilient pressure of a device against the inside of oneof the parts of the stick. This device, while able to revolve, is firmlyconnected with the other part of the stick, the locking or release beingachieved by turning the two parts relative to each other.

The above mentioned methods of locking the parts are complicated andthus expensive to produce. Further, there is no practicable means ofeliminating the tolerance (variation of measurements) in respect of thediameters of the sticks, the control of which the rolling mills alwaysreserve to themselves. There is hence always the risk that a lockingdevice may be difficult to manipulate because of tightness in one tube(stick) or it may be too loose in another, the result being that thelocking will not be fully effective or may not work at all, since thenecessary frictional contact between the locking device and the tube(stick) is not being obtained. The locking devices are comparativelylight in construction and thus the locking may not be fully effective onaccount of tear and wear or breakage.

The object of this invention is to produce a strong, everlasting clampdevice for holding two telescopically sliding tubes in adjustedposition. Accordingly the system using a springy device has beendiscarded and has been replaced by a strong non-springy frictionalclamp. At the same time means has been provided to eliminate tolerance,if any, in the diameters of the tubes or sticks.

The accompanying drawing illustrates an example of the invention.

In the drawing:

Fig. 1 is an exploded vertical section of the locking device without thetwo tubes or sticks.

Fig. 2 is a vertical section of the locking device, the two parts of thestick being locked together.

Fig. 3 is a section along the line A--A in Fig. 1.

Fig. 4 is a section similar to Fig. 3 but showing the frictional clampmade in a different way.

Fig. 5 shows the locking device according to Fig. 1, seen from theoutside and turned in a position of 90 in relation to Fig. 1.

In the drawing, 1 indicates the lower part of the tube or stick and 2the top part. It will be seen that the lower part I is telescopicallyslidable inside the upper tube 2. A relatively thin cylindrical piece 3is soldered or welded on to the upper end of the lower tube section I.The cylindrical piece 3 has a short threaded spindle 4 which projectsupwardly from the center of the piece 3, the upper end of the spindle 4being formed to provide a conical portion 5, the sides of which have aninclination of approximately 15 to the axis of the cone.

The threaded spindle 4 is adapted to screw into a cylindrical case orbody portion 6 which is provided with a central threaded hole 1 whichextends axially through the case 6 and is adapted to receive the spindle4. The diameter of the case 6 is such that it can easily be pushed up ordown in the upper tube section 2, sliding gently along the inside of thetube. In order to eliminate tolerance, if any, as regards the diameterof the tube, the case ii is provided with a vertical slit 8 which makesthe lower end of the case slightly springy. If there is any spacebetween the case and the tube, a wedge is driven into the split 8 tospring the lower portion of the case 6 out to the proper diameter. Whenproperly fitted, the case 6 slides easily in the tube section v2 withfrictional contact but without binding. The resilience provided by theslit 3 is not for the purpose of locking the two tube sections togetherand has nothing to do with the springy pressure effect utilized inpreviously known constructions, as pointed out above.

In accordance with the invention, the body portion or case 6 is providedwith a transverse slot 9 which is located diametrically opposite to theslit 8 and extends in to approximately the middle of the case. Theheight of the slot 9 (in an axial direction) is about 5 millimeters andthe top and bottom sides are substantially parallel to one another andpreferably perpendicular to the axis of the case 5. The slot 9 ispreferably in the upper portion of the case 6 while the longitudinalslit 8 is in the lower portion. In the slot 9 there is loosely placed africtional clamp In which is of semi-circular shape and, as will bedescribed below, may be pressed out radially to engage the inside of thetube section 2. The size and shape of the frictional clamp H] areapproximately the same as those of the radial slot 9, so

that the clamp Ill substantially fills the slot with a loose fit. On theinside vertical surface of the clamp N) there is provided an arcuatebore or recess H which is of conical shape with an inclinationcorresponding to that of the cone 5,

clamp namely, about 15. The mean radius of the semi-circular conicalbore H is somewhat smaller than the radius of the hole 1 extendingaxially through the case 6. Thus, when the frictional ll] is placed inthe groove or slot 9 with 3' its outer surface flush with the outside ofthe case 6, the inside curved surface of the clamp II] will project alittle way into the hole i, as shown in Figs. 1 and 3.

It will be seen that when the threaded spindle 4 is screwed into thethreaded bore '1 by rotation of the cylindrical piece 3 relative to thecase 6, the conical upper end portion 5 of the spindle 4 will engage theinside curved surface of the frictional clamp member in and force theclamp radially outwardly so as to project [beyond the outer surface ofth case 6.. Positive 'non-springy movement of the clamp member isthereby provided. 7

As stated above, the frictional clamp l fits loosely the slot 9. To keepthe clamp In from coming out of the groove when the case 6 is removedfrom the tube section 2, the clamp is preferably provided with a narrowinclined. radial groove i2. When the frictional clamp has been put in.its place, the case 6 is dented, as indicated at I3, to form aprojection which extends into the inclined. groove E2 of the clamp Illand is of such size as to prevent the clamp from coming all the way outon the slot 9 while permittingv its radial movement, as described above.

Fig. 4 shows a modified example of the invention in which the singlefrictional clamp H! has been replaced by three radial frictional clampmembers i i which are of any suitable cross-sectional shape, for exampleround or square pins. Alternatively, they may be of approximately theshape shown in Fig. 3, in which case two clamp members would be used andwould be placed in diametrically opposed position.

The operation of the device is as follows. The case 6 provided with thefrictional clamp member iii is, as shown by Fig. 2, screwed on to thespindle Al. of the cylindrical part 3 which is fixed to the lower stickportion i. Thereupon, the case 6 and the engagement portion of the stickI are pushed longitudinally into the upper tube portion 2.v The caseslides easily into the tube with slight frictional engagement. In orderto lock the parts i and 2 together, the tube sections are turnedslightly relative to one another to cause the spindle to screw itselfinto the case 6. The conical part of the spindle engages the insideconical bore ll of the frictional clamp i0 and thereby forces thefrictional clamp outwardly and presses it into engagement with the tube2 which will thereby instantly be locked firmly to the lower part of thetube 5. Thus the locking is achieved by the pressure of the frictionalclamp iii against the tube 2 which is engaged on the opposite side bythe solid portion of the case 6. The opposed gripping forces are thustransmitted through the clamp ill, the spindle i and the case 6 in suchmanner that a positive looking pressure is provided without any springypressure eifect.

In order to regulate the length of the stick, the tubular sections areturned slightly in the opposite direction. The spindl ti is therebyscrewed down, thus releasing the pressure of the frictional clamp andpermitting relative longitudinal movement of the two tubular sections.If the twotubular sections are pulled completely apart, the clampingdevice remains completely assembled on the upper end of the lowersection and can readily be slid back into the upper section when it isdesired to put the two sections back together.

While the case 6 is shown in the drawing. (Fig. 2) as being detachablyscrewed on to the spindle 4, the cone -5 can, of course, readily belengthened so as to reach beyond the case 6 and provide it with a stopdevice in such a way that the spindle 4 can-not come out of the case 6.Still other modifications of the device will be apparent to thoseskilled in th art within the scope of the invention as defined by theappended claims.

What I claim and desire to secure by Letters Patent is:

1. An adjustable ski-stick comprising two telescopically sliding tubesone inside the other and means for locking the tubes in adjustedrelation comprising a cylindrical case frictionally slidable inside theouter section and having a threaded axial bore and an opening extendingradially from said here to the outer periphery of said case intermediateits ends, a clamp member loosely received in said opening and movableradially therein, a threaded spindle secured to the end of the innertube and adapted to screw freely into the threaded bore of. the saidcase, said spindle having a conical portion adapted to engage the clampmember and move it positively outwardly into locking engagement with theinner surface of the outer tube upon relative rotation of the case andspindle to screw the spindie further into the bore of the case, saidcase having resilient means for maintaining slight frictional engagementbetween the case and. the outer tube section when the said clamp memberis released, said resilient means and clamp member acting independentlyof one another.

2. An adjustable ski-stick consisting of two telescopically slidingtubes one inside the other and means for locking the tubes in adjustedrelation comprising a cylindrical. case frictionally slidable insidethe. outer section and having a threaded axial bore and a transverseopening extending approximately half way through the case from one sidethereof and having upper and lower sides which are substantiallyparallel to one another and perpendicular to the. axis of the case, asemi-circular clamp member loosely received in said opening and havingon its inner side a semi-circular notch corresponding in shape to asegment of a cone, a threaded spin.- d'le. secured to the end of theinner tube and adapted to screw into the threaded bore of the case, saidspindle having at its upper end a conical portion adapted to engage theconical notch of the clamp member and move said member positivelyoutwardly into locking engagement with the outer tube upon relative.rotation of the case and spindle to screw the spindle further into thebor of the case.

3.. An adjustable ski-stick according to claim 2, in which the clampmember is provided with a narrow, inclined radial groove and the case isprovided with a protuberance projecting into the groove to retain theclamp member and case in assembled relation while permitting theirrelative movement.

OLE WALTER JENSEN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PAIENTS Number Name Date 339,844 Kintz Sept. 18, 18881,357,714 Lane Nov.v 2, 1920

